[Heartbeat/Synthetics] Ability to map resolving DNS server(s)

[BenB196]

Describe the enhancement:

I would like the ability to track/map the DNS server(s) which were used for resolving a host.

Describe a specific use case for the enhancement or feature:

Today, Heartbeat/synthetics tracks the time to resolve a host via the field resolve.rtt.us. An issue/gap here though, is it doesn't track which DNS server(s) it attempted to contact for this. If I provide a list of DNS servers to Heartbeat/synthetics, it is my understand that Heartbeat will follow the OSes DNS server order (ex: Linux tries DNS servers in the order they're in in resolve.conf). It would be helpful for troubleshooting to know which DNS server Heartbeat/synthetics got a response from, to help troubleshoot potential DNS related issues.

[elasticmachine]

Pinging @elastic/uptime (Team:Uptime)

[andrewvc]

Thanks for the ping @BenB196 , it's a great idea, but candidly one we haven't had much interest in. Would you be interested in submitting a patch? We'd be glad to review one, but it probably won't land on our roadmap anytime soon without broader interest.

[andrewvc]

By the way @BenB196 I am curious to hear more about your use case etc, if you'd like to connect on a call sometime reach out on the community slack channel , we'd love to hear from you. You can find it here: https://elasticstack.slack.com/archives/CNRTHRCLD

[botelastic]

Hi!
We just realized that we haven't looked into this issue in a while. We're sorry!

We're labeling this issue as Stale to make it hit our filters and make sure we get back to it as soon as possible. In the meantime, it'd be extremely helpful if you could take a look at it as well and confirm its relevance. A simple comment with a nice emoji will be enough :+1.
Thank you for your contribution!